Factors influencing the immediate postoperative outcome in operated head injured patients in Ibadan, Nigeria

Abstract

Introduction: The injured brain is subjected lo anaesthetic agents and various intravenous fluids which may exacerbate haemodynamic instability, increase cerebral blood volume and intracranial pressure. Objective: The study examined factors that influenced the immediate postoperative outcome in head injured patients who underwent general anaesthesia in a tertiary health care facility. Methods: The demographic and outcome data of all head injured patients who had neurosurgical procedures under general anaesthesia in our centre between January and December 2010 were compiled prospectively. Outcome was measured using the Glasgow Coma Scale (GCS), good outcome was defined as an improvement in the GCS/recovery while poor outcome as worsening of GCS / mortality post operatively. The data were analyzed using SPSS 16.0 and p value was set at 0.05. Results: Ninety nine patients were recruited. The patients' median age was 37.0 years and 81.8% were males. The most affected age group was 17- 49 years. Indications for surgery were compound depressed skull fracture 28.3%, intracerebral haematoma 17.2%, subdural 35.4% and extradural haematoma 13.1 % and impacted intracranial foreign body 6%. Eighty six percent of the patients had their head injury following road traffic accident. Fatality rate was 16.2%. Outcome was poor in patients with severe head injury (13%)compared with patients with mild (1.1%) and moderate head injur)' (2%) p=0.001, and poor in American Society of Anaesthesiologist's (ASA) 3 (9%) and 4 (6%) classification compared to ASA 2 (1%) (p=0.0069). Outcome was also poor in patients with intracerebral haematoma (9%) and acute subdural haematoma (2%) compared to that of depressed skull fracture (1%) (P=0.002) and in patients with intraoperative hypotension (13.1%) compared with those with normal blood pressure (1 %) (p=0.0() 1). Conclusion: Road traffic accident is the leading cause of head injur)', increasing ASA, decreasing GCS, type of cranial lesion and intraoperative hypotension are some of the factors affecting outcome in operated head injuries. Efforts should be made to reduce the incidence of intra operative hypotension to increase good outcome in operated head injured patients